/*

 * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "classfile/resolutionErrors.hpp"

#include "memory/resourceArea.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/safepoint.hpp"

#include "utilities/hashtable.inline.hpp"

// add new entry to the table

void ResolutionErrorTable::add_entry(int index, unsigned int hash,

                                     constantPoolHandle pool, int cp_index, Symbol* error)

{

  assert_locked_or_safepoint(SystemDictionary_lock);

  assert(!pool.is_null() && error != NULL, "adding NULL obj");

  ResolutionErrorEntry* entry = new_entry(hash, pool(), cp_index, error);

  add_entry(index, entry);

}

// find entry in the table

ResolutionErrorEntry* ResolutionErrorTable::find_entry(int index, unsigned int hash,

                                                       constantPoolHandle pool, int cp_index)

{

  assert_locked_or_safepoint(SystemDictionary_lock);

  for (ResolutionErrorEntry *error_probe = bucket(index);

                         error_probe != NULL;

                         error_probe = error_probe->next()) {

  if (error_probe->hash() == hash && error_probe->pool() == pool()) {

      return error_probe;;

    }

  }

  return NULL;

}

void ResolutionErrorEntry::set_error(Symbol* e) {

  assert(e == NULL || _error == NULL, "cannot reset error");

  _error = e;

  if (_error != NULL) _error->increment_refcount();

}

// create new error entry

ResolutionErrorEntry* ResolutionErrorTable::new_entry(int hash, ConstantPool* pool,

                                                      int cp_index, Symbol* error)

{

  ResolutionErrorEntry* entry = (ResolutionErrorEntry*)Hashtable<ConstantPool*, mtClass>::new_entry(hash, pool);

  entry->set_cp_index(cp_index);

  NOT_PRODUCT(entry->set_error(NULL);)

  entry->set_error(error);

  return entry;

}

void ResolutionErrorTable::free_entry(ResolutionErrorEntry *entry) {

  // decrement error refcount

  assert(entry->error() != NULL, "error should be set");

  entry->error()->decrement_refcount();

  Hashtable<ConstantPool*, mtClass>::free_entry(entry);

}

// create resolution error table

ResolutionErrorTable::ResolutionErrorTable(int table_size)

    : Hashtable<ConstantPool*, mtClass>(table_size, sizeof(ResolutionErrorEntry)) {

}

// RedefineClasses support - remove matching entry of a

// constant pool that is going away

void ResolutionErrorTable::delete_entry(ConstantPool* c) {

  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");

  for (int i = 0; i < table_size(); i++) {

    for (ResolutionErrorEntry** p = bucket_addr(i); *p != NULL; ) {

      ResolutionErrorEntry* entry = *p;

      assert(entry->pool() != NULL, "resolution error table is corrupt");

      if (entry->pool() == c) {

        *p = entry->next();

        free_entry(entry);

      } else {

        p = entry->next_addr();

      }

    }

  }

}

// Remove unloaded entries from the table

void ResolutionErrorTable::purge_resolution_errors() {

  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");

  for (int i = 0; i < table_size(); i++) {

    for (ResolutionErrorEntry** p = bucket_addr(i); *p != NULL; ) {

      ResolutionErrorEntry* entry = *p;

      assert(entry->pool() != (ConstantPool*)NULL, "resolution error table is corrupt");

      ConstantPool* pool = entry->pool();

      assert(pool->pool_holder() != NULL, "Constant pool without a class?");

      ClassLoaderData* loader_data =

              pool->pool_holder()->class_loader_data();

      if (!loader_data->is_unloading()) {

        p = entry->next_addr();

      } else {

        *p = entry->next();

        free_entry(entry);

      }

    }

  }

}